function popUp(URL, w, h) {
    day = new Date();
    id = day.getTime();
    var winX = (screen.width - w) / 2;
    var winY = (screen.height - h) / 2;
    eval("page" + id + " = window.open(URL, '" + id + "', 'toolbar=0,scrollbars=1,location=0,status=1,menubar=0,resizable=0,left=" + winX + ",top=" + winY + ",width=" + w + ",height=" + h + "');");
}